Re: [Qemu-devel] [PATCH 4/4] vhost-scsi: add an ioctl interface to get target id

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Jan 19, 2015 at 09:23:38PM +0800, arei.gonglei@huawei.com wrote:
> From: Gonglei <arei.gonglei@huawei.com>
> 
> Because vhost-scsi module do not support VHOST_SCSI_GET_TPGT
> at present, so I use "#if 0" handle it, and set the target
> default to 1. In addition, channel and lun both are 0 for
> bootable vhost-scsi device.
> 
> Signed-off-by: Gonglei <arei.gonglei@huawei.com>
> Signed-off-by: Bo Su <subo7@huawei.com>

OK but let's see the kernel patch get accepted first.

> ---
>  hw/scsi/vhost-scsi.c           | 39 +++++++++++++++++++++++++++++++++++++++
>  include/hw/virtio/vhost-scsi.h |  1 +
>  2 files changed, 40 insertions(+)
> 
> diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
> index dc9076e..a7cd420 100644
> --- a/hw/scsi/vhost-scsi.c
> +++ b/hw/scsi/vhost-scsi.c
> @@ -201,6 +201,36 @@ static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq)
>  {
>  }
>  
> +static int vhost_scsi_get_target_id(VHostSCSI *s, Error **errp)
> +{
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
> +    const VhostOps *vhost_ops = s->dev.vhost_ops;
> +    struct vhost_scsi_target backend;
> +    int ret;
> +
> +    memset(&backend, 0, sizeof(backend));
> +    pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
> +    ret = vhost_ops->vhost_call(&s->dev, VHOST_SCSI_GET_TPGT, &backend);
> +    /* Fixme: wait vhost-scsi module supporting VHOST_SCSI_GET_TPGT */
> +#if 0
> +    if (ret < 0) {
> +        error_setg_errno(errp, -ret,
> +                         "vhost-scsi: failed to get the target id");
> +        return ret;
> +    }
> +#elseif
> +    if (ret < 0) {
> +        error_report("Warning: vhost-scsi failed to get the target id: %s",
> +                     strerror(-ret));
> +        /* set default target to 1 */
> +        backend.vhost_tpgt = 1;
> +    }
> +#endif
> +
> +    s->target = backend.vhost_tpgt;
> +    return 0;
> +}
> +
>  static void vhost_scsi_realize(DeviceState *dev, Error **errp)
>  {
>      VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
> @@ -251,6 +281,15 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
>          return;
>      }
>  
> +    /* At present, channel and lun both are 0 for bootable vhost-scsi disk */
> +    s->channel = 0;
> +    s->lun = 0;
> +    if (vhost_scsi_get_target_id(s, &err)) {
> +        error_propagate(errp, err);
> +        close(vhostfd);
> +        return;
> +    }
> +
>      error_setg(&s->migration_blocker,
>              "vhost-scsi does not support migration");
>      migrate_add_blocker(s->migration_blocker);
> diff --git a/include/hw/virtio/vhost-scsi.h b/include/hw/virtio/vhost-scsi.h
> index c0056c2..a6bd031 100644
> --- a/include/hw/virtio/vhost-scsi.h
> +++ b/include/hw/virtio/vhost-scsi.h
> @@ -49,6 +49,7 @@ enum vhost_scsi_vq_list {
>  #define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
>  #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
>  #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
> +#define VHOST_SCSI_GET_TPGT _IOW(VHOST_VIRTIO, 0x45, struct vhost_scsi_target)
>  
>  #define TYPE_VHOST_SCSI "vhost-scsi"
>  #define VHOST_SCSI(obj) \
> -- 
> 1.7.12.4
>